sql-delete

I tried execute this sql sentence delete from reclamo r where exists ( select 1 from reclamo r join cliente c on r.cod_cliente = c.cod_cliente join localidad l on c.cod_localidad = l.cod_localidad where l.descripcion = 'San Justo'); for remove all the claims made by customers of the town of 'San justo' but it says "Error Code: 1064. You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'r where exists ( select 1 from reclamo r join cliente c on r.cod_cliente' at line 2" anyone know how I can fix these errors?

I have a table of scores, which is made of 2 fields: name and high score . Something like this: ----------------------- | name | score | ----------------------- | John | 2450 | ----------------------- | Alice | 2420 | ----------------------- ... etc I need to delete all the rows till the top 50 scores. Is it possible without creating another temporary table ? please try this delete from scores_tbl Where id not in (select * from (select id from scores_tbl order by score desc limit 50) as temp) Create an auto increment field alter table scores add id int unique auto_increment not null; This will

I have two table to contain state (state_table) and city (city_table) of countries The city table is having state_id to relate it with state_table Both the tables are already having data in it. Now the problem City table contains multiple entries of a city within one state. And another cities may or may not have the same city name as well e.g.: cityone will have 5 occurrence in the city table with stateone and 2 occurrence with statetwo So how will I write a query to keep one city for each state and delete the rest? Schema follows CREATE TABLE IF NOT EXISTS `city_table` ( `id` int(11) NOT NULL

I can use select * from sent_txts s LEFT JOIN received_txts r ON s.msg_link_id = r.id WHERE r.action_id = 6; top select matching rows, How can I write a query to delete the matching rows on both sides? Something like delete sent_txts s LEFT JOIN received_txts r ON s.msg_link_id = r.id WHERE r.action_id = 6; Disclaimer: I do not have access to a mysql database to test at the moment, but I think you can use: delete s, r from send_txts s left join received_txts r on s.msg_link_id = r.id where r.action_id = 6; See mysql's delete documentation for more information. A better method might be to put a

Hi I have the following SQL Query which gives me Scheme_Id which exist both in ProjectSchemes and Schemes table. I want to delete all records from Schemes table which have no record to ProjectSchemes table. How can I do so? Please help. I'm using MSSQL select scheme_id from Schemes where Scheme_Id in(select s.Scheme_Id from Projects p inner join ProjectSchemes ps on ps.Project_Id=p.Project_Id inner join Schemes s on s.Scheme_Id=ps.Scheme_Id) I'm trying to do the following but it's not working. Not working means no records affected but as I checked my Schemes table there are so many records

I have these tables: event (evt_id, evt_code, reg_id) magnitude (mag_id, evt_id, value) trace (trace_id, pt_id) point (pt_id, evt_id) I want to delete all rows from all tables related to evt_id=1139 . How do I do it? Justin Pihony If you have control over your schema, I would make the schema use cascading deletes . From the article (the more pertinent portion translated for your example) CREATE TABLE point ( pt_id integer PRIMARY KEY, evt_id integer REFERENCES event ON DELETE CASCADE ) If you have cascades set up, then you can just delete from the main event table and all the other tables will

I'm trying to make sql who will delete all duplicate titles BUT must delete duplicates with these conditions: must delete only duplicates with same object_id must keep only the newest record (biggest topic_id ) (topic_id is the unique id for every topic AI) So far I've done that (testing with select...) SELECT topic_id,object_id,title,url,date FROM topics GROUP BY title HAVING ( COUNT(title) > 1) ORDER BY topic_id DESC But doesn't meet the conditions. I'm using mysql. In MySQL , you cannot specify the target table to a DML operation in a subquery (unless you nest it more than one level deep,

Can I say that one of many ways to optimize mysql is to reduce the number of queries? If that so, can I do this: - Select "data" => $A from table X - Update $A from table Y - Delete $A from table X in one query? You can't reduce the number of queries - they all do different things - but you could reduce the number of round trips to the database and the number of parses by wrapping it all as a PLSQL function. However you can't select the data after you've deleted it.....but consider: CREATE PROCEDURE s_u_d(a) BEGIN UPDATE tab_x SET tab_x.avalue=1 WHERE tab_x.another=a; DELETE FROM tab_y WHERE